1. Field of the Invention
The present invention relates to a rotating device configured to rotationally drive a recording disk.
2. Description of the Related Art
Progress is being made in reducing the size and increasing the data capacity of a disk driving apparatus such as a hard disk drive. Such a disk driving apparatus is mounted in various kinds of electronic devices. In particular, progress is being made in mounting such a disk driving apparatus in portable electronic devices such as laptop personal computers, portable music players, and so forth. As conventional techniques, a disk driving apparatus has been proposed as described in Japanese Patent Application Laid Open No. 2010-205378, for example.
Such a disk driving apparatus described in Japanese Patent Application Laid Open No. 2010-205378 employs, as a driving magnet, a magnet mainly composed of rare-earth materials (which will also be referred to as a “rare-earth magnet” hereafter). However, from the viewpoint of the global scarcity of some of these magnetic materials, there is a demand for a technique for contributing to improved resource saving with respect to such magnetic materials. In addition, there is a demand for a technique for further reducing the driving current required to rotationally drive such a rotating device.
In such a situation, there is a demand for a technique for effectively employing such magnetic materials, or otherwise a technique for reducing the driving current required to rotationally drive such a rotating device. However, conventional rotating devices use a large quantity of some kinds of magnetic materials such as rare-earth materials etc., which is contrary to the trend of resource saving. Alternatively, such conventional rotating devices cannot contribute to further reducing the driving current.